Efficacy and Safety Study of Neu2000KWL for Acute Ischemic Stroke Patients Within 6 Hours of Onset (Salfaprodil)

The present study is to investigate safety and efficacy of Neu2000, a multi-target neuroprotectant acting as a moderate NR2B-selective NMDA receptor antagonist and potent antioxidant, in acute ischemic stroke patients within 6 hours of onset. Compared to NMDA antagonists or antioxidants, improved efficacy and therapeutic time window of Neu2000 have been well documented in four animal models of stroke. Notable Safety of Neu2000 has been demonstrated in 168 human subjects conducted in the US and China as well as animals. In the present phase II study, patients with acute ischemic stroke within 6 hours of onset would be assigned randomly to one of four groups as follows: * Group A receiving 2.75g Neu2000KWL for 5 days * Group B receiving 5.25g Neu2000KWL for 5 days * Group C receiving 6.00g Neu2000KWL for 5 days * Group D receiving placebo for 5 days Patients will receive intravenous infusion of the clinical study drug twice a day at 12±1 hour intervals for 5 days.